using UnityEngine;

namespace Mirror.Examples.BilliardsPredicted
{
    public class WhiteBallPredicted : NetworkBehaviour
    {
        public LineRenderer dragIndicator;
        public Rigidbody rigidBody;
        public float forceMultiplier = 2;
        public float maxForce = 40;

        // remember start position to reset to after entering a pocket
        Vector3 startPosition;

        // cast mouse position on screen to world position
        bool MouseToWorld(out Vector3 position)
        {
            Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
            Plane plane = new Plane(Vector3.up, transform.position);
            if (plane.Raycast(ray, out float distance))
            {
                position = ray.GetPoint(distance);
                return true;
            }
            position = default;
            return false;
        }

        void Awake()
        {
            startPosition = transform.position;
        }

        [ClientCallback]
        void OnMouseDown()
        {
            // enable drag indicator
            dragIndicator.SetPosition(0, transform.position);
            dragIndicator.SetPosition(1, transform.position);
            dragIndicator.gameObject.SetActive(true);
        }

        [ClientCallback]
        void OnMouseDrag()
        {
            // cast mouse position to world
            if (!MouseToWorld(out Vector3 current)) return;

            // drag indicator
            dragIndicator.SetPosition(0, transform.position);
            dragIndicator.SetPosition(1, current);
        }

        [ClientCallback]
        void OnMouseUp()
        {
            // cast mouse position to world
            if (!MouseToWorld(out Vector3 current)) return;

            // calculate delta from ball to mouse
            // ball may have moved since we started dragging,
            // so always use current ball position here.
            Vector3 from = transform.position;

            // debug drawing: only works if Gizmos are enabled!
            Debug.DrawLine(from, current, Color.white, 2);

            // calculate pending force delta
            Vector3 delta = from - current;
            Vector3 force = delta * forceMultiplier;

            // there should be a maximum allowed force
            force = Vector3.ClampMagnitude(force, maxForce);

            // forward the event to the local player's object.
            // the ball isn't part of the local player.
            NetworkClient.localPlayer.GetComponent<PlayerPredicted>().OnDraggedBall(force);

            // disable drag indicator
            dragIndicator.gameObject.SetActive(false);
        }

        // reset position when entering a pocket.
        // there's only one trigger in the scene (the pocket).
        [ServerCallback]
        void OnTriggerEnter(Collider other)
        {
            rigidBody.position = startPosition;
            rigidBody.Sleep(); // reset forces
            // GetComponent<NetworkRigidbodyUnreliable>().RpcTeleport(startPosition);
        }

        [ClientCallback]
        void OnGUI()
        {
            // have a button to reply exactly the same force in every hit for easier testing.
            if (GUI.Button(new Rect(10, 150, 200, 20), "Hit!"))
            {
                // hit with a slight angle so the red balls spread out in all directions
                Vector3 force = Vector3.ClampMagnitude(new Vector3(10, 0, 600), maxForce);
                NetworkClient.localPlayer.GetComponent<PlayerPredicted>().OnDraggedBall(force);
            }
        }
    }
}